1587475 - Page faults and Lock contention on the render backend from memory allocations

Status: NEW

(Core :: Graphics: WebRender, defect, P3)

Description

[Nicolas Silva [:nical]]

Looking at page faults with perf, we have a fair amount of them on the render backend thread:

• PrimitiveCluster::push
• webrender::scene_building::SceneBuilder::create_primitive
• webrender::picture::PrimitiveList::push
• webrender::batch::BatchBuilder::add_prim_to_batch

I also see a lot of lock contention from memory allocation, Jeff tells me we don't have jemalloc arenas on the render backend threads, we should have them, probably.

I saw some hashmap code in TileCacheInstance::pre_update showing up which I didn't expect.

Looks like there is room for better avoiding/preallocating/recycling allocations in general, so we should do another pass of that.